Dissertation > Excellent graduate degree dissertation topics show

Photovoltaic Device Based Small-Molecules-Doped Polymer

Author: YinMing
Tutor: ZhangXinPing
School: Beijing University of Technology
Course: Optics
Keywords: small-molecule-doped polymer semiconductors annealing temperature composition ratio photovoltaic device phase separation and crystalization absorptionand photoluminescence spectroscopy exciplex
CLC: TN304.5
Type: Master's thesis
Year: 2012
Downloads: 94
Quote: 0
Read: Download Dissertation

Abstract


Compared to traditional inorganic semiconductor materials, organicsemiconductors have advantages of low cost, low pollution, easy preparation, andflexible thin-film devices. However, the biggest problem that limits the applications oforganic materials is the low carrier mobility in organic semiconductors. The lowcarrier mobility will reduce significantly the efficiency of the optoelectronic devices,thus limiting the possible applications. Therefore, to improve the charge transferefficiency in organic materials is one of the key issues for the development of organicoptoelectronics. Using blends of organic semiconductors to construct hetero-junctionstructures is one of the effective and practical approaches. Furthermore, time-resolvedspectroscopy enables understanding of the photophysics related to energy transfer,charge generation, charge transport, charge separation and combination processes.This thesis is based on the blend materials of a small molecule semiconductorperylene N,N9-bis(1-ethylpropyl)-3,4,9,10-perylenebis (dicarboximide)(EPPTC) anda Polyfluorene derivative of Poly(9,9’-dioctylfluorene-co-benzothiadiazole)(F8BT).Bulk hetero-junction structures form in the blend film and photophysical propertieshave been studied using steady-state and time-resolved spectroscopy, as well asmicorscopic characterization. Photovoltaic devices using the blend materials havebeen prepared and the conversion efficiency has been measured at different annealingtemperatures and different composite ratios, where changing the annealingtemperatures or the composite ratio was used to modify the phase-separation, themorphology, and the crystalization properties of the molecules in the blend film. Thethesis is arranged as follows:1. The influence of the annealing temperature on the surface morphology of theF8BT: EPPTC blend film has been characterized by the atomic force microscopy(AFM), where the annealing process modified the phase separation between the smalland the polymer molecules and the crystalization of the EPPTC small molecules.2. The spectroscopic characteristics of the blends of F8BT: EPPTC have beenstudied using the absorption and photoluminescence spectra measured at differentannealing temperatures and different composite ratios between the two kinds ofmolecules. Furthermore, the crystalization properties of EPPTC are found to beenhanced with increasing the annealing temperature and the concentration of EPPTC. 3. By changing the composition ratio of the F8BT: EPPTC blend and theannealing temperature, the external quantum efficiency of the photovoltaic devicebased on the bulk hetero-junction structure was characterized systematically. It isfound that the annealing process and modification of the composite ratio in the blendsare effective methods to address the photophysics in the organic hetero-junctionstructures and to optimize the optoelectronic properties of the photovoltaic devices.

Related Dissertations

  1. Na, K and Mg of preparation and properties of doped ZnO thin films,TB383.2
  2. Copper diffusion barrier layer self-assembly process research,TN405
  3. Fabrication and Yellow Luminescence Study of Single-crystalline SnO2 Nanostructure,TB383.1
  4. Synthesis of Suspension Grafting PEB-g-MAN and Its Toughening Effect on SAN Resin,TQ320.7
  5. The Synthesis and Characterization of Functional Polyimide,O633.22
  6. Fluorene small molecule organic electroluminescent device of its role exciplex,TN383.1
  7. Electrochemical Preparation of Polypyrrole Film and Preliminary Exploration of Device,O484.1
  8. Mixed concrete mechanical properties and durability test study,TU528
  9. Gene Expression of Adiponectin and Adiponectin Receptor in Rats Fed Different Fatty Acids Ratios Diet,R151
  10. Application of Poly(3,4-ethylenedioxythiophene) in Organic Light-emitting Diode,TN383.1
  11. Researching on the Functional Layer and the Mutually Doped Transitional Layer of OLED,TN312.8
  12. The Research of Corundum-mullite Multiphase Kiln’s Stability of Thermal Shock Resistance and Design Optimization,TQ174
  13. Styrene - acrylonitrile copolymer sequences gradient structure ~ (13) C-NMR Characterization and Dynamic Monte Carlo simulation,O631.3
  14. The Research of Baotou Iron and Steel Company of Steel Slag Taken as Road Building Material,U414
  15. Study on Photoelectric Properties of Novel Rare Earth Complexes in Doped Systems,O482.31
  16. The Effect of Extract from Silkworm Chrysalis on the Fatty Acids Spectra of High-fat Rat’s Livers,R575.5
  17. Computer Simulation for the Effect of the Dormant/activate Reaction on the Sequence Structure of Atom Transfer Radical Copolymer,O631.3
  18. The Effects of Hot Stretching on Morphology and Properties of PET/PE/CB Conductive Composites,TM24
  19. A Study on Predicting Model of the Fluxes and Profiles of Amino Acids in the Duodenum Digesta of Inner Mongolian White Cashmere Goats,S827
  20. Studies on Synthesized, Characterization and Photoelectric Properties of Starburst Metal Complexes,O641.4
  21. Orientation of the Discotic Liquid Crystals and Their Application in the Optoelectronic Device,TN104.3

CLC: > Industrial Technology > Radio electronics, telecommunications technology > Semiconductor technology > General issues > Material > Organic semiconductors
© 2012 www.DissertationTopic.Net  Mobile